- ID:
- ivo://CDS.VizieR/J/ApJ/771/85
- Title:
- Dynamical masses of z~2 quiescent galaxies
- Short Name:
- J/ApJ/771/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using stellar kinematics measurements, we investigate the growth of massive, quiescent galaxies from z~2 to today. We present X-Shooter spectra from the UV to NIR and dynamical mass measurements of five quiescent massive (>10^11^M_{sun}_) galaxies at z~2. This triples the sample of z>1.5 galaxies with well-constrained ({delta}{sigma}<100km/s) velocity dispersion measurements. From spectral population synthesis modeling we find that these galaxies have stellar ages that range from 0.5 to 2Gyr, with no signs of ongoing star formation. We measure velocity dispersions (290-450km/s) from stellar absorption lines and find that they are 1.6-2.1 times higher than those of galaxies in the Sloan Digital Sky Survey at the same mass. Sizes are measured using GALFIT from Hubble Space Telescope Wide Field Camera 3 H_160_ and UDS K-band images. The dynamical masses correspond well to the spectral energy distribution based stellar masses, with dynamical masses that are ~15% higher.
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- ID:
- ivo://CDS.VizieR/J/ApJ/715/310
- Title:
- Early stages of star formation in IRDCs
- Short Name:
- J/ApJ/715/310
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Identified as extinction features against the bright Galactic mid-infrared background, infrared dark clouds (IRDCs) are thought to harbor the very earliest stages of star and cluster formation. In order to better characterize the properties of their embedded cores, we have obtained new 24um, 60-100um, and submillimeter continuum data toward a sample of 38 IRDCs. The 24um Spitzer images reveal that while the IRDCs remain dark, many of the cores are associated with bright 24um emission sources, which suggests that they contain one or more embedded protostars. Combining the 24um, 60-100um, and submillimeter continuum data, we have constructed broadband spectral energy distributions (SEDs) for 157 of the cores within these IRDCs and, using simple graybody fits to the SEDs, have estimated their dust temperatures, emissivities, opacities, bolometric luminosities, masses, and densities. Based on their Spitzer/Infrared Array Camera 3-8um colors and the presence of 24um point-source emission, we have separated cores that harbor active, high-mass star formation from cores that are quiescent. The active "protostellar" cores typically have warmer dust temperatures and higher bolometric luminosities than the more quiescent, perhaps "pre-protostellar," cores. Because the mass distributions of the populations are similar, however, we speculate that the active and quiescent cores may represent different evolutionary stages of the same underlying population of cores. Although we cannot rule out low-mass star formation in the quiescent cores, the most massive of them are excellent candidates for the "high-mass starless core" phase, the very earliest in the formation of a high-mass star.
- ID:
- ivo://CDS.VizieR/J/MNRAS/436/3759
- Title:
- ECDFS sources optical/IR counterparts
- Short Name:
- J/MNRAS/436/3759
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sub-mJy radio population is a mixture of active systems, that is star-forming galaxies (SFGs) and active galactic nuclei (AGNs). We study a sample of 883 radio sources detected at 1.4GHz in a deep Very Large Array survey of the Extended Chandra Deep Field-South that reaches a best rms sensitivity of 6{mu}Jy. We have used a simple scheme to disentangle SFGs, radio-quiet (RQ), and radio-loud (RL) AGNs based on the combination of radio data with Chandra X-ray data and mid-infrared observations from Spitzer. We find that at flux densities between about 30 and 100{mu}Jy, the radio population is dominated by SFGs (~60%) and that RQ AGNs become increasingly important over RL ones below 100 {mu}Jy. We also compare the host galaxy properties of the three classes in terms of morphology, optical colours and stellar masses. Our results show that both SFG and RQ AGN host galaxies have blue colours and late-type morphology while RL AGNs tend to be hosted by massive red galaxies with early-type morphology. This supports the hypothesis that radio emission in SFGs and RQ AGNs mainly comes from the same physical process: star formation in the host galaxy.
- ID:
- ivo://CDS.VizieR/J/A+A/557/A66
- Title:
- Effective SEDs of IR galaxies at various z
- Short Name:
- J/A+A/557/A66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent studies have revealed a strong correlation between the star formation rate (SFR) and stellarmass of the majority of star-forming galaxies, the so-called star-forming main sequence. An empirical modeling approach (the 2-SFM framework) that distinguishes between the main sequence and rarer starburst galaxies is capable of reproducing most statistical properties of infrared galaxies, such as number counts, luminosity functions, and redshift distributions. In this paper, we extend this approach by establishing a connection between stellar mass and halo mass with the technique of abundance matching. Based on a few simple assumptions and a physically motivated formalism, our model successfully predicts the (cross-)power spectra of the cosmic infrared background (CIB), the crosscorrelation between CIB and cosmic microwave background (CMB) lensing, and the correlation functions of bright, resolved infrared galaxies measured by Herschel, Planck, ACT, and SPT.We use this model to infer the redshift distribution of CIB-anisotropies and of the CIBxCMB lensing signal, as well as the level of correlation between CIB-anisotropies at different wavelengths. Material (effective spectral energy distributions, differential emissivities of halos, relations between Mh and SFR) associated to this model is available at http://irfu.cea.fr/Sap/Phocea/Page/index.php?id=537
- ID:
- ivo://CDS.VizieR/J/A+A/456/881
- Title:
- EIS: infrared deep public survey
- Short Name:
- J/A+A/456/881
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is part of the series presenting the final results obtained by the ESO Imaging Survey (EIS) project. It presents new J and Ks data obtained from observations conducted at the ESO 3.5m New Technology Telescope (NTT) using the SOFI camera. These data were taken as part of the Deep Public Survey (DPS) carried out by the ESO Imaging Survey program, significantly extending the earlier optical/infrared EIS-DEEP survey presented in a previous paper of this series. The DPS-IR survey comprises two observing strategies: shallow Ks observations providing nearly full coverage of pointings with complementary multi-band (in general UBVRI) optical data obtained using ESO's wide-field imager (WFI) and deeper J and Ks observations of the central parts of these fields. Currently, the DPS-IR survey provides a coverage of roughly 2.1 square degrees (~300 SOFI pointings) in Ks with 0.63 square degrees to fainter magnitudes and also covered in J, over three independent regions of the sky. The goal of the present paper is to briefly describe the observations, the data reduction procedures, and to present the final survey products which include fully calibrated pixel-maps and catalogs extracted from them. The astrometric solution with an estimated accuracy of <0.15" is based on the USNO catalog and limited only by the accuracy of the reference catalog. The final stacked images presented here number 89 and 272, in J and Ks, respectively, the latter reflecting the larger surveyed area. The J and Ks images were taken with a median seeing of 0.7" and 0.8". The images reach a median 5 sigma limiting magnitude of J_AB~23.06 as measured within an aperture of 2", while the corresponding limiting magnitude in Ks_AB is ~21.41 and ~22.16mag for the shallow and deep strategies. Although some spatial variation due to varying observing conditions is observed, overall the observed limiting magnitudes are consistent with those originally proposed. The quality of the data has been assessed by comparing the measured magnitude of sources at the bright end directly with those reported by the 2MASS survey and at the faint end by comparing the counts of galaxies and stars with those of other surveys to comparable depth and to model predictions. The final science-grade catalogs together with the astrometrically and photometrically calibrated co-added images are available at CDS.
- ID:
- ivo://CDS.VizieR/J/A+A/452/119
- Title:
- EIS: infrared observations of CDF-S and HDF-S
- Short Name:
- J/A+A/452/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents infrared data obtained from observations carried out at the ESO 3.5m New Technology Telescope (NTT) of the Hubble Deep Field South (HDF-S) and the Chandra Deep Field South (CDF-S). These data were taken as part of the ESO Imaging Survey (EIS) program, a public survey conducted by ESO to promote follow-up observations with the VLT. In the HDF-S field the infrared observations cover an area of ~53 square arcmin, encompassing the HST WFPC2 and STIS fields, in the JHKs passbands. The seeing measured in the final stacked images ranges from 0.79" to 1.22" and the median limiting magnitudes (AB system, 2" aperture, 5sigma detection limit) are J_AB~23.0, H_AB~22.8 and K_AB~23.0mag. Less complete data are also available in JKs for the adjacent HST NICMOS field. For CDF-S, the infrared observations cover a total area of ~100 square arcmin, reaching median limiting magnitudes (as defined above) of J_AB~23.6 and K_AB~22.7mag. For one CDF-S field H-band data are also available. This paper describes the observations and presents the results of new reductions carried out entirely through the un-supervised, high-throughput EIS Data Reduction System and its associated EIS/MVM C++-based image processing library developed, over the past 5 years, by the EIS project and now publicly available. The paper also presents source catalogs extracted from the final co-added images which are used to evaluate the scientific quality of the survey products, and hence the performance of the software. This is done comparing the results obtained in the present work with those obtained by other authors from independent data and/or reductions carried out with different software packages and techniques.
- ID:
- ivo://CDS.VizieR/J/MNRAS/351/1290
- Title:
- ELAIS: final band-merged catalogue
- Short Name:
- J/MNRAS/351/1290
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog represents the final band-merged European Large-Area ISO Survey (ELAIS) Catalogue at 6.7, 15, 90 and 175{mu}m, and the associated data at U, g', r', i', Z, J, H, K and 20cm. Details about the origin of the survey, the observations, data reduction and optical identification are described in the paper. In addition to fluxes in the radio, infrared and optical passbands, spectroscopic redshifts are tabulated, where available. For the N1 and N2 areas, the Isaac Newton Telescope ugriz Wide Field Survey permits photometric redshifts to be estimated for galaxies and quasars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/358/333
- Title:
- ELAIS optical ident. at 15um & 1.4GHz
- Short Name:
- J/MNRAS/358/333
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multi-wavelength properties and catalogue of the 15{mu}m and 1.4GHz radio sources detected in the European Large Area ISO Survey (ELAIS) areas N1 and N2. Using the optical data from the Wide Field Survey we use a likelihood ratio method to search for the counterparts of the 1056 and 691 sources detected at 15{mu}m and 1.4GHz, respectively, down to flux limits of S_15_=0.5mJy and S_1.4_GHz=0.135mJy.
- ID:
- ivo://CDS.VizieR/J/AJ/105/853
- Title:
- Energy distributions of radio galaxies
- Short Name:
- J/AJ/105/853
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Far-infrared observations of 140 radio galaxies from the 3CR and B2 catalogs are presented. The galaxies span a range of over four order of magnitude in the radio power, from weak nuclear sources in nearby galaxies, to powerful FR II doubled-lobed sources at moderate redshift. Scanned or pointed observations with IRAS detect 38 of the radio galaxies in at least one waveband; 21 are detected at both 60 and 100 {mu}m. The strength of the far-infrared emission is more closely correlated with core radio emission than with total radio emission, and it is independent of the absolute visual magnitude of the host galaxy. The more luminous 3CR galaxies have warmer far infrared emission than the less luminous B2 galaxies. The relationship between radio and far-infrared luminosity is determined in a way that is insensitive to the large number of infrared nondetections. Radio galaxies have far-infrared emission with similar color temperatures to normal ellipticals; however the inferred amounts of cold interstellar material are typical of gas-rich galaxies. Infrared luminous radio galaxies are rare. Only one in 10^5^ ellipticals with M_V_<-17 has a strong enough radio core to have 10^11^ L_Sun_ of far-infrared emission. Indirect arguments indicates that far-infrared emission in radio galaxies represents star formation that is more closely tied to the active nucleus than to the global properties of the galaxy. The far-infrared luminosity function shows good continuity between radio galaxies and radio loud quasars.
- ID:
- ivo://CDS.VizieR/J/ApJ/890/7
- Title:
- Environment of galaxies in the 5 CANDELS fields
- Short Name:
- J/ApJ/890/7
- Date:
- 17 Jan 2022 00:15:58
- Publisher:
- CDS
- Description:
- We present a robust method, weighted von Mises kernel density estimation, along with boundary correction to reconstruct the underlying number density field of galaxies. We apply this method to galaxies brighter than Hubble Space Telescope/F160w<=26 AB mag in the redshift range 0.4<=z<=5 in the five CANDELS fields (GOODS-N, GOODS-S, EGS, UDS, and COSMOS). We then use these measurements to explore the environmental dependence of the star formation activity of galaxies. We find strong evidence of environmental quenching for massive galaxies (M>~10^11^M_{sun}_) out to z~3.5 such that an overdense environment hosts >~20% more massive quiescent galaxies than an underdense region. We also find that environmental quenching efficiency grows with stellar mass and reaches ~60% for massive galaxies at z~0.5. The environmental quenching is also more efficient than stellar mass quenching for low-mass galaxies (M>~10^10^M_{sun}_) at low and intermediate redshifts (z<~1.2). Our findings concur thoroughly with the "overconsumption" quenching model where the termination of cool gas accretion (cosmological starvation) happens in an overdense environment and the galaxy starts to consume its remaining gas reservoir in depletion time. The depletion time depends on the stellar mass and could explain the evolution of environmental quenching efficiency with stellar mass.